Process for manufacturing an improved web material by the in-situ measurement and adjustment of ion concentration

ABSTRACT

A process having the steps of producing the web material with the papermaking machine; measuring a molar amount of a monovalent inorganic ionizable cation species (MIICS) in the web material; measuring a molar amount of a divalent inorganic ionizable cation species (DIICS) in the web material; calculating a molar ratio of the measured molar amount of the MIICS to the measured molar amount of the DIICS in the web material; determining if the molar ratio of MIICS to DIICS is about less than or equal to 10; and, if the molar ratio of MIICS to DIICS is greater than about 10, adding an amount of DIICS to the papermaking machine to adjust the molar ratio of MIICS to DIICS so the web material adhering to the Yankee drum drying system has a molar ratio of MIICS to DIICS of about less than or equal to 10, is disclosed.

FIELD OF THE INVENTION

The present invention relates to the production of tissue and towelpaper web structures that incorporate the use of a Yankee dryer. Theseprocesses relate to the specific ionic characteristics present in thefibrous materials used to make these web structures and adjusting themolar ratio of certain ions present in the fibrous materials that makethe Yankee creping adhesive more stable and controllable. Thisstabilization is achieved by adjusting the molar ratios of divalent andmonovalent ions at various locations in the pulp making and papermakingprocesses.

BACKGROUND OF THE INVENTION

Web materials having enhanced softness, absorbency, and strength(temporary and permanent), such as tissue and towel products, aredesired by consumers. To this end, work continues and attempts to findnew ways produce these web materials to better meet this consumerdesire. “Web material(s)”, “fibrous web(s)”, and “fibrous structure(s)”are all intended to be utilized interchangeably throughout this documentto reference structures that result in, or are useful for, tissue and/ortowel products.

“Softness” is the tactile sensation that is the result of a user'sperception based on the web material drape over their hand, the way thesurface of the web material feels against their fingers and/or how theimplement feels as it is folded or crumpled in their hand. This tactilesensation is a result of a combination of several physical properties ofthe paper sheet including the bulk, strength, and stretchability of thepaper.

“Creping” is a process that mechanically foreshortens a fibrousstructure in the machine and/or cross-machine directions to enhance thesoftness, bulk and stretchability of the final web material.Foreshortening refers to the reduction in length of a dry (having aconsistency of at least about 90% and/or at least about 95%) fibrous webwhich occurs when energy is applied to the dry fibrous web in such a waythat the length of the fibrous web is reduced and the fibers in thefibrous web are rearranged with an accompanying disruption offiber-fiber bonds.

A creped web substrate can be formed with a flexible blade (a “crepingblade”) placed against a heated drying cylinder such as a Yankee dryer(also called a “Yankee drum drying system”herein). A partially dryfibrous structure is adhered to the surface of a Yankee dryer and thenrotates with the surface of the Yankee dryer until contact with thecreping blade removes it from the surface of the Yankee dryer. Thedegree to which the fibrous structure is adhered to the surface of theYankee dryer prior to creping can be considered a key factor todetermine the degree of softness, bulk, and stretchability exhibited bythe fibrous structure after creping.

It is understood that the paper machine (also referred to as apapermaking machine throughout) operating conditions and specific unitoperations of a paper machine can have a great impact on Yankee crepingadhesive appearance and performance. Furthermore, the interface betweenthe Yankee dryer surface and the web material is a thin film comprisingan agglomeration of materials that results from both materials directlyadded to the process via the Yankee dryer creping adhesive, but alsomaterials that are carried to the Yankee dryer via the web material, thefibers contained in the web material, and the specific operating systemand equipment used in making these web materials. The Yankee crepingadhesive is therefore both constructed of and influenced by the pulpsused to make the structure, inorganic contaminants and chemicals sold tomanage and control these materials.

Since the creping process has an impact on the softness, bulk, andstretchability of the resulting final product intended for the webmaterial, the creping process is considered a key transformation stepcommonly used in the manufacture of tissue, facial and towel grades ofpaper. Without desiring to be bound by theory, it is believed thatcreping creates micro and macro folds in the web material that canincrease the bulk, softness and absorbency of the web material.

To facilitate a good crepe quality, many papermakers add a crepingadhesive formulation to the Yankee dryer prior to contact with thepartially dry fibrous structure to enable good adhesion. The crepingadhesive formulation may comprise one or more adhesive components suchas water-soluble adhesive polymers, one or more release agentcomponents, and/or other desired additives that may achieve the desiredpartially dry fibrous structure/Yankee dryer contact and impart desiredproperties to the resulting web material. The chemical mixture appliedto the surface of the Yankee dryer prior to adhesion of the partiallydry fibrous structure is commonly referred to as a “creping adhesive”.

The level of adhesion of the partially dry fibrous structure to theYankee dryer surface is also of importance as it influences the abilityand capability of a partially dry fibrous structure to dry during itsshort time in contact with the Yankee dryer. Higher levels of adhesionpermit better heat transfer but can also affect the ability of a driedpartially dry fibrous structure to be released from the Yankee dryersurface, and therefore creped. Increased drying capability is desired,as improving the drying capability may allow the machine to operate athigher speeds.

Historically, before the development of the creping adhesive, adhesionof the partially dry fibrous structure to the Yankee dryer surface wasaccomplished through the presence of naturally occurring hemicellulosepresent in the individual pulp fibers. Hemicellulose deposits have beenobserved forming on the Yankee dryer surface can vary and, at times thetackiness of the hemicellulose changes to cause these deposits tocontain fiber fragments picked out of the fibrous structure, resultingin a heavy film, holes in the sheet, sheet breaks, and poor crepequality.

Another problem associated with the use of the creping adhesive is anexcessive build-up of the creping adhesive on the Yankee dryer surface.While some amount of buildup of the creping adhesive on the Yankee dryeris essential to protect the dryer shell, excessive buildup can producestreaks, which impact the profile of adhesion across the width of theYankee dryer surface. This buildup can result in sheet bumps, wrinkles,wet spots and sheet breaks in the finished web material. A second blade,known as a cleaning blade can scrape the Yankee dryer surface to removeexcess creping adhesive and any other residue left behind on the Yankeedryer surface. This requires extra process steps to change both thecreping and the cleaning blades frequently to prevent excessive buildupof adhesive coating and ensure good crepe quality.

One of skill in the art can use polyamidoamine-epichlorohydrin resins(PAE resins) as creping adhesives. PAE resins can incorporatehypophosphorous acid and its salts as an antioxidant and/or a stabilizerin polymeric formulations, polyamides, and alkyd resins. Polymersstabilized by hypophosphorous acid and its salts are all water-insolublematerials.

While the Yankee creping adhesive choices are adapted to create a morereliable Yankee creping adhesive to solve crepe quality concerns, tissuesheet creping reliability improvement continues to be a focus area ofincreasing importance.

Additionally, the reduction of water consumption in pulp and papermakingoperations is a global goal that has been a long-term focus for costreduction reasons. However, water consumption reduction is also criticalto attain new sustainability/environmental goals. Those skilled in theart recognize that reduction of water consumption involves the increasedclosure of a papermaking water circuit. Closure of the papermakingprocess water circuit generally results in the build-up of non-processelements, most of which are cationic and anionic in nature. The build-upof fines may also take place, but these are anionic in nature. Thebuildup of cationic compounds leads to poor paper formation andadversely affects the production throughput and paper machinerunnability, due to sheet breaks and their resulting production losseswhen they exceed the isoelectric point.

Closure of the papermaking water system can result in higher suspendedsolids, higher dissolved solids, increased temperature and reduceddissolved oxygen. This can lead to increased corrosion, increaseddeposition, increased microbiological activity, reduction in additiveefficiency and reduction in finished product quality.

Those skilled in the art recognize that papermaking operations require astable and slightly anionic environment to allow proper fiber-to-fiberbonding and web material sheet formation. Wood pulp fibers used to makethe web materials discussed herein are generally anionic in nature dueto certain residual functional groups, namely carboxylic acid andphenolic hydroxyl carried over with the non-extracted hemicellulose andlignin fragments. Carboxylic acids are weakly dissociated and thecarboxylate moiety (—COO⁻) present on wood pulp fibers acts as ananionic site for cation exchange at the proportion of one mole offunctional group on the pulp. As the pH increases, carboxylic acidgroups in wood pulp dissociate until the amount of alkali added is thesame as the amount of existing charged groups. The carboxylate acts as aweak-acid cation exchanger that is not highly dissociated and will notreadily exchange H⁺ ions as strong creping adhesives (resins) do. Inother words, wood pulp fibers exhibit a weak-acid resin (WAR) character.

WAR exchangers require the presence of some alkaline species to reactwith the more tightly bond hydrogen ions of the creping adhesive as inthe reaction:Ca(HCO₃)₂+2(R—H⁺)

(2R⁻)—Ca⁺⁺+2(H₂CO₃)

Those skilled in the art recognize that it is common in a tissue/towelpapermaking operation to add alkaline agents to the pulper or whitewater complex for pH control, better slushing of the pulp bales, andimproved fiber swelling. Those skilled in the art will also recognizethat it is common in tissue and towel papermaking operations to addacidic agents to the pulper or white water complex for pH control. Thechoice of whether a papermaker adds acid or alkaline agents depends uponthe papermaking strength additives, water supply source and qualityand/or other papermaking or product considerations. The exchange processis a neutralization reaction with the alkaline HCO₃ ⁻ neutralizing theH⁺ of the resin. WAR, such as wood pulp or cellulose, will splitalkaline salts (NaHCO₃) but not non-alkaline salts (NaCl or Na₂SO₄).Weak-acid cation ion exchange resins are used to remove the cationsassociated with high alkalinity, such as the counter-ions of CO₃ ⁻², OFFand HCO₃ ⁻, and low in dissolved CO₂ and sodium.

In making wood pulp for a papermaking operation, during the unitoperations of digesting and bleaching, the anionic sites areelectrically compensated by a counter-ion that is cationic in nature.This can include typically sodium, calcium and/or magnesium, amongothers in minor amounts. Different pulps may have a larger or smalleramount of anionic sites present that are fully or partially neutralizedeven in the presence of excess counter-ions, which are not bond to pulpbut present as residual ash. The amount of bonding ions available candepend on the wood raw material, the pulping, bleaching and washingoperational conditions.

Those skilled in the art recognizes that pulp beating (i.e., refining)can increase the accessible surface charge groups, allowing easieraccess to such groups in the fibers. Those of skill in the art willreadily recognize that pulp beating and other pulp handling techniques(i.e., refining) can increase the accessible surface charge groups,allowing easier access to such groups in the fibers, while the totalisoelectric charge changes with beating or refining. The amount of metalions in the pulp is, however, in the same order as the amount of acidgroups.

The processes used for the manufacture of certain pulp fibers can resultin saleable pulps that lack divalent ions commonly observed in past pulpfibers. When these pulps are dried, they show a significant ashreduction versus their peers. Further, these pulps also show a muchhigher molar ratio of monovalent ions bound to the carboxyl groupscompared to divalent ions. This is problematic as local pulp millsincorporate closed water systems and/or are located or re-located toparts of the world where soft water is used in the pulp making process.

It has also been observed that fibrous pulps having a higher percentageof monovalent ions attached to the surface may result in significantrunnability problems in tissue and towel processes due to Yankeedryer/creping adhesive adhesion issues. It is also believed that thesefibers have a lower chemical efficiency than competitive pulp fibers.

Further, while not being bound to any particular theory, it is believedthat the “Dreshfield effect” can be linked to the rationale as to whypulp mills with a higher degree of closed water systems and/orpapermaking operations with substantially closed water systems haveYankee creping adhesive-related issues. By way of example, the Yankeedrying process in tissue and towel machines happens quite fast (inseconds) with a starting dryness of around 30-60% and ending in adryness in excess of 90%. During this drying process, the ions presentin the partially dry fibrous structure (i.e., web material) migrate viathe Dreshfield effect. Not be bound to theory, the Dreshfield effectprovides that water migrates from the core of a partially dry fibrousstructure to the outer part of the partially dry fibrous structurecarrying soluble and colloidal materials. These soluble and colloidalmaterials then concentrate at the outer layers of the partially dryfibrous structure. As one of the sides of the partially dry fibrousstructure is adhered to the surface of the Yankee dryer, the soluble andcolloidal materials disposed on the adhered surface of the partially dryfibrous structure can quickly react with the creping adhesive disposedupon the surface of the Yankee dryer. It is believed that specific iontypes present in the soluble and colloidal materials disposed upon thesurface of the partially dry fibrous structure deleteriously react withthe Yankee creping adhesive. This results in a web material havingdefects present therein being removed (i.e., creped”) from the surfaceof the Yankee dryer. It was surprisingly discovered that having thecorrect ion types present within the partially dry fibrous structurewould clearly mitigate these ineffective interactions and likely resultin a better quality web material being creped off the surface of theYankee dryer.

Thus, it would be a clear advantage for tissue and towel manufacturingsystems to provide a method that addresses the impact of the changingionic nature of the incoming fiber sheet (i.e., web material) on Yankeecreping adhesive. It would also be a clear advantage to provide aprocess that mitigates this impact via an ion exchange process wherebyspecific inorganic ions in defined specific molar ratios can be used tomitigate the observed deleterious Yankee creping issues and therebycreate a more robust system via ion exchange of the web material. Itwould also be advantageous to provide a method of producing crepedtissue and towel paper products that exhibit improved processcapability, improved Yankee dryer reliability, improved dryingefficiency, and improved tissue/towel product crepe quality. Further, itwould be an advantage to provide a tissue making process that is morecapable of mitigating process upsets that may result from changes inpulp supply and/or pulp suppliers because the pulp raw material supplyused to produce these tissue and towel products having different levelsof cationic salt or mono/divalent metal ions due to the use of closedloop water systems or pulp supplies that are naturally deficient inhardness and/or divalent cations.

SUMMARY OF THE INVENTION

The present disclosure provides a process for manufacturing a webmaterial on a papermaking machine having a Yankee drum drying system.The process comprises the steps of: a) producing the web material withthe papermaking machine; b) measuring a molar amount of a monovalentinorganic ionizable cation species (MIICS) in the web material; c)measuring a molar amount of a divalent inorganic ionizable cationspecies (DIICS) in the web material; d) calculating a molar ratio of themeasured molar amount of the MIICS to the measured molar amount of theDIICS in the web material; e) determining if the molar ratio of MIICS toDIICS is about less than or equal to 10; and, f) if the molar ratio ofMIICS to DIICS is greater than about 10, adding an amount of DIICS tothe papermaking machine to adjust the molar ratio of MIICS to DIICS sothe web material adhering to the Yankee drum drying system has a molarratio of MIICS to DIICS of about less than or equal to 10.

The present disclosure also provides a process for manufacturing a webmaterial on a papermaking machine having a Yankee drum drying system.The process comprises the steps of: a) producing the web material withthe papermaking machine; b) measuring a molar amount of a monovalentinorganic ionizable cation species (MIICS) in the web material; c)measuring a molar amount of a divalent inorganic ionizable cationspecies (DIICS) in the web material; d) calculating a molar ratio of themeasured molar amount of the MIICS to the measured molar amount of theDIICS in the web material; e) determining if the molar ratio of MIICS toDIICS is about less than or equal to 10; and, f) if the molar ratio ofMIICS to DIICS is greater than about 10, applying an amount of DIICS toa surface of the Yankee drum drying system to adjust the molar ratio ofMIICS to DIICS so the web material adhering to the Yankee drum dryingsystem has a molar ratio of MIICS to DIICS of about less than or equalto 10.

The present disclosure further provides a process for manufacturing aweb material on a papermaking machine having a Yankee drum dryingsystem. The process comprises the steps of: a) producing the webmaterial with the papermaking machine; b) measuring a molar amount of amonovalent inorganic ionizable cation species (MIICS) in the webmaterial; c) measuring a molar amount of a divalent inorganic ionizablecation species (DIICS) in the web material; d) calculating a molar ratioof the measured molar amount of the MIICS to the measured molar amountof the DIICS in the web material; e) determining if the molar ratio ofMIICS to DIICS is about less than or equal to 10; and, f) if the molarratio of MIICS to DIICS is greater than about 10, applying an amount ofDIICS to the web material after the web material has been adhered to asurface of the Yankee drum drying system to adjust the molar ratio ofMIICS to DIICS so the web material adhered to the Yankee drum dryingsystem has a molar ratio of MIICS to DIICS of about less than or equalto 10.

The present disclosure yet further provides a process for manufacturinga web material on a papermaking machine having a Yankee drum dryingsystem. The process comprises the steps of: a) providing the papermakingmachine with a white water loop section, the white water loop sectionproviding the papermaking machine with an aqueous stream; b) producingthe web material with the papermaking machine; c) measuring a molaramount of a monovalent inorganic ionizable cation species (MIICS) in theweb material; d) measuring a molar amount of a divalent inorganicionizable cation species (DIICS) in the web material; e) calculating amolar ratio of the measured molar amount of the MIICS to the measuredmolar amount of the DIICS in the web material; f) determining if themolar ratio of MIICS to DIICS is about less than or equal to 10; and, g)if the molar ratio of MIICS to DIICS is greater than about 10, adding anamount of DIICS to the white water loop section of the papermakingmachine to adjust the molar ratio of MIICS to DIICS in the aqueousstream to about less than or equal to 50.

The present disclosure still further provides a process formanufacturing a web material on a papermaking machine having a Yankeedrum drying system. The process comprises the steps of: a) providing thepapermaking machine with a fresh water makeup system, the fresh watermakeup system providing the papermaking machine with an aqueous stream;b) producing the web material with the papermaking machine; c) measuringa molar amount of a monovalent inorganic ionizable cation species(MIICS) in the web material; d) measuring a molar amount of a divalentinorganic ionizable cation species (DIICS) in the web material; e)calculating a molar ratio of the measured molar amount of the MIICS tothe measured molar amount of the DIICS in the web material; f)determining if the molar ratio of MIICS to DIICS is about less than orequal to 10; and, g) if the molar ratio of MIICS to DIICS is greaterthan about 10, adding an amount of DIICS to the fresh water makeupsystem of the papermaking machine to adjust the molar ratio of MIICS toDIICS in the aqueous stream is about less than or equal to 50.

The present disclosure still yet further provides a process formanufacturing a web material on a papermaking machine having a Yankeedrum drying system. The process comprises the steps of: a) supplying theYankee drum drying system with a creping adhesive; b) applying thecreping adhesive to a surface of the Yankee drum drying system; c)producing the web material with the papermaking machine; d) measuring amolar amount of a monovalent inorganic ionizable cation species (MIICS)in the web material; e) measuring a molar amount of a divalent inorganicionizable cation species (DIICS) in the web material; f) calculating amolar ratio of the measured molar amount of the MIICS to the measuredmolar amount of the DIICS in the web material; g) determining if themolar ratio of MIICS to DIICS is about less than or equal to 10; and, h)if the molar ratio of MIICS to DIICS is greater than about 10, adding anamount of DIICS to the creping adhesive so that the web material uponcontact with the creping adhesive disposed upon the surface of theYankee drum drying system DIICS has a molar ratio of MIICS to DIICS ofabout less than or equal to 10.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a side elevational view of an exemplary papermaking systemsuitable for use with the present disclosure; and,

FIG. 2 is a side elevational view of an exemplary Yankee drying drumsystem and creping process suitable for use with the present disclosure.

DETAILED DESCRIPTION OF THE INVENTION

The present disclosure is applicable to creped tissue and towel paper ingeneral and includes but is not limited to conventionally wet pressedcreped tissue and towel paper, high bulk pattern densified creped tissuepaper and towel and high bulk, uncompacted creped tissue and towelpaper.

The present disclosure provides a method to predict when a particularpulp and/or pulp manufacturing process can negatively impact the Yankeedryer adhesive of a tissue and towel manufacturing system. Thisdisclosure also provides a method to proactively manage the Yankee dryeradhesive coating and the impact of inorganic ions present in the webmaterial adhered thereto by proactively managing, adding, and/orcontrolling the cationic salts present in the fibrous pulp at the pulpmanufacturing location, at the wet end of the papermaking operation, oranywhere in the tissue and/or towel manufacturing process (up to andincluding the Yankee creping adhesive spray booms) to facilitate ionexchange to a favorable molar ratio of monovalent inorganic ionizablecation species to divalent inorganic ionizable cation species of lessthan or equal to 10. This ion exchange process and mechanism can also beeffective for use with PAE based creping adhesives and other Yankeecreping adhesive chemistries including polyvinyl alcohols, polyamines,polyvinyl acetates, polyacrylamides, and polyethyleneimines.

The present disclosure also provides a process for manufacturing atissue and/or towel web material on a papermaking machine having aheadbox wet ingredient mixing system and a Yankee drum drying system,wherein the Yankee drum drying system is supplied by a creping adhesive.A divalent inorganic ionizable cation species can be added to the pulpmanufacturing or papermaking process to maintain a molar ratio ofmonovalent inorganic ionizable cation species to divalent inorganicionizable cation species in the solid phase of the incoming structure tothe Yankee dryer is less than or equal to 10. It is believed that thision exchange process and mechanism is equally effective on PAE basedadhesives and other Yankee creping adhesive chemistries includingpolyvinyl alcohols, polyamines, polyvinyl acetates, polyacrylamides, andpolyethyleneimines.

By adding a divalent inorganic ionizable cation species anywhere in thepulp manufacturing or papermaking processes that allows ion exchangewhen the molar ratio of monovalent ions to divalent ions is greater than10, it was surprisingly found that Yankee creping adhesive appearanceand performance significantly improved from a non-treated state. Theimprovement in Yankee creping adhesive performance can be measured byincreased Yankee creping adhesive appearance and tack, improved crepingblade life, improved crepe quality, improved paper machine reliabilityand improved tissue product attributes.

It was also surprisingly found that the molar ratio of monovalent ionsto divalent ions can be measured in the papermaking white water loop,pulper(s), papermaking chests, or other aqueous papermaking and stockstreams and used as a predictive tool for Yankee creping adhesiveperformance and/or for the control of dissolved divalent ion addition tomaintain the molar ratio of monovalent inorganic ionizable cationspecies to divalent inorganic ionizable cation species to less than orequal to 50 in the white water loop, and a molar ratio of monovalentinorganic ionizable cation species to divalent inorganic ionizablecation species to less than or equal to 10 in tissue machine pulper(s),papermaking chests, or other aqueous papermaking and stock streams.These ions can be ionizable into an aqueous solution and therefore becombined with counter ions that are easily dissociated in water.

Papermaking

The web materials for use as tissue and/or towel products made by thetechniques described herein can be made by any suitable process known inthe art. Such processes can incorporate a cylindrical dryer such as aYankee dryer.

FIG. 1 is a simplified, schematic representation of an exemplarycontinuous web material manufacturing process and machine (i.e., a‘papermaking machine’) incorporating a Yankee dryer. A process andassociated equipment 50 for making a fibrous structure can generallycomprise supplying an aqueous dispersion of fibers (a fibrous furnishformed from a papermaking pulp) to a headbox 52 which can be of anyconvenient design. From the headbox 52, the aqueous dispersion of fibersis delivered to a first foraminous member 54 (a Fourdrinier wire) toproduce an embryonic fibrous web 56.

The first foraminous member 54 may be supported by a breast roll 58 anda plurality of return rolls 60 of which only two are shown. The firstforaminous member 54 can be propelled in the direction indicated bydirectional arrow 62 by a drive means (not shown). Optional auxiliaryunits and/or devices commonly associated fibrous structure makingmachines and with the first foraminous member 54 can include formingboards, hydrofoils, vacuum boxes, tension rolls, support rolls, wirecleaning showers, and the like.

After the aqueous dispersion of fibers is deposited onto the firstforaminous member 54, an embryonic fibrous web 56 is formed by theremoval of a portion of the aqueous dispersing medium by techniques wellknown to those skilled in the art. Vacuum boxes, forming boards,hydrofoils, and the like are useful in effecting water removal. Theembryonic fibrous web 56 may travel with the first foraminous member 54about return roll 60 and is brought into contact with a molding member,such as a deflection member 64, which may also be referred to as asecond foraminous member. While in contact with the deflection member64, the embryonic fibrous web (i.e., web material) 56 can be deflected,rearranged, and/or further dewatered.

The deflection member 64 may be in the form of an endless belt. In thissimplified representation, deflection member 64 passes around and aboutdeflection member return rolls 66 and impression nip roll 68 and maytravel in the direction indicated by directional arrow 70. Associatedwith deflection member 64, but not shown, may be various support rolls,other return rolls, cleaning means, drive means, and the like known tothose skilled in the art that may be commonly used in fibrous structuremaking machines.

Regardless of the physical form which the deflection member 64 takes,whether it is an endless belt as just discussed or some other embodimentsuch as a stationary plate for use in making hand sheets or a rotatingdrum for use with other types of continuous processes, it must havecertain physical characteristics. For example, the deflection member maytake a variety of configurations such as belts, drums, flat plates, andthe like.

First, the deflection member 64 may be foraminous. That is to say, itmay possess passages connecting its first surface 72 (or “upper surface”or “working surface”; i.e. the surface with which the embryonic fibrousweb is associated, sometimes referred to as the “embryonic fibrousweb-contacting surface”) with its second surface 74 (or “lower surface”;i.e., the surface with which the deflection member return rolls areassociated). In other words, the deflection member 64 may be constructedin such a manner that when water is caused to be removed from theembryonic fibrous web 56, as by the application of differential fluidpressure, such as by a vacuum box 76, and when the water is removed fromthe embryonic fibrous web 56 in the direction of the deflection member64, the water can be discharged from the system without having to againcontact the embryonic fibrous web 56 in either the liquid or the vaporstate.

Second, the first surface 72 of the deflection member 64 may compriseone or more ridges. The ridges may be made by any suitable material. Forexample, a resin may be used to create the ridges. The ridges may becontinuous, or essentially continuous. The ridges may be arranged toproduce the fibrous structures of the present invention when utilized ina suitable fibrous structure making process. The ridges may bepatterned. The ridges may be present on the deflection member at anysuitable frequency to produce the fibrous structures of the presentinvention. The ridges may define within the deflection member aplurality of deflection conduits. The deflection conduits may bediscrete, isolated, deflection conduits.

The deflection conduits of the deflection member 64 may be of any sizeand shape or configuration so long as the deflection conduits produce aplurality of line elements in the fibrous structure produced thereby.The deflection conduits may repeat in a random pattern or in a uniformpattern. Portions of the deflection member 64 may comprise deflectionconduits that repeat in a random pattern and other portions of thedeflection member 64 may comprise deflection conduits that repeat in auniform pattern. The ridges of the deflection member 64 may beassociated with a belt, wire or other type of substrate. The woven beltmay be made by any suitable material, for example polyester, known tothose skilled in the art.

After the embryonic fibrous web 56 has been associated with thedeflection member 64, fibers within the embryonic fibrous web 56 aredeflected into the deflection conduits present in the deflection member64. In one example of this process step, there is essentially no waterremoval from the embryonic fibrous web 56 through the deflectionconduits after the embryonic fibrous web 56 has been associated with thedeflection member 64 but prior to the deflecting of the fibers into thedeflection conduits. Further water removal from the embryonic fibrousweb 56 can occur during and/or after the time the fibers are beingdeflected into the deflection conduits. Water removal from the embryonicfibrous web 56 may continue until the consistency of the embryonicfibrous web 56 associated with deflection member 64 is increased to fromabout 25% to about 35%. Once this consistency of the embryonic fibrousweb 56 is achieved, then the embryonic fibrous web 56 is referred to asan intermediate fibrous web 84. During the process of forming theembryonic fibrous web 56, sufficient water may be removed, such as by anoncompressive process, from the embryonic fibrous web 56 before itbecomes associated with the deflection member 64 so that the consistencyof the embryonic fibrous web 56 may be from about 10% to about 30%.

Any convenient means conventionally known in the papermaking art can beused to dry the intermediate fibrous web 84. Examples of such suitabledrying process include subjecting the intermediate fibrous web 84 toconventional (vacuum/press drying) and/or air flow-through dryers and/orYankee dryers. Tissue and Towel webs may be one density or may be formedto have multiple densities.

In one example of a drying process, the intermediate fibrous web 84 inassociation with the deflection member 64 passes around the deflectionmember return roll 66 and travels in the direction indicated bydirectional arrow 70. The intermediate fibrous web 84 may first passthrough an optional pre-dryer 86. This pre-dryer 86 can be aconventional flow-through dryer (hot air dryer) well known to thoseskilled in the art. Optionally, the pre-dryer 86 can be a socalledcapillary dewatering apparatus. In such an apparatus, the intermediatefibrous web 84 passes over a sector of a cylinder havingpreferential-capillary-size pores through its cylindricalshaped porouscover. Optionally, the pre-dryer 86 can be a combination capillarydewatering apparatus and flow-through dryer. The quantity of waterremoved in the pre-dryer 86 may be controlled so that a pre-driedfibrous web 88 exiting the pre-dryer 86 has a consistency of from about30% to about 98%. The pre-dried fibrous web 88, which may still beassociated with deflection member 64, may pass around another deflectionmember return roll 66 and as it travels to an impression nip roll 68. Asthe pre-dried fibrous web 88 passes through the nip formed betweenimpression nip roll 68 and a surface of a Yankee dryer 90, the ridgepattern formed by the top surface 72 of deflection member 64 isimpressed into the pre-dried fibrous web 88 to form a line elementimprinted fibrous web 92.

The imprinted fibrous web 92 can then be adhered to the surface of theYankee dryer 90 where it can be dried to a consistency of at least about95%. The imprinted fibrous web 92 can then be foreshortened by crepingthe imprinted fibrous web 92 with a creping blade 94 to remove theimprinted fibrous web 92 from the surface of the Yankee dryer 90resulting in the production of a creped fibrous structure 96 inaccordance with the present invention. The creped fibrous structure 96may be subjected to post processing steps such as calendaring, tuftgenerating operations, and/or embossing and/or converting.

The fibrous structure may be incorporated into a single- or multi-plysanitary tissue product. The sanitary tissue product may be in roll formwhere it is convolutedly wrapped about itself with or without theemployment of a core. In one example, the sanitary tissue product may bein individual sheet form, such as a stack of discrete sheets, such as ina stack of individual facial tissue.

Yankee Dryer

FIG. 2, shows an example of a standard process for the final drying andcreping of a web material using a Yankee dryer. In this example, thetissue web is brought to the Yankee dryer on a flat, wire, fabric orbelt and pressed to the Yankee dryer 205. The web material being driedby the Yankee dryer may have an incoming moisture content ranging from10% to 90%. Further, this moisture may not be uniform within the sheetby design, especially using current structured papermaking technologies.

The creping adhesive can be applied to the surface of the Yankee dryer205 via spray nozzles. The transfer and impression fabric 201 can carrythe formed, dewatered and partially dried web material 202 aroundturning roll 203 to the nip between press roll 204 and Yankee dryer 205.A supplemental lower carrier 216 may also be employed to carry the webmaterial in a sandwich fashion, which may be particularly useful underconditions of higher web dryness. The fabric 201, web material 202, andYankee dryer 205 move in the directions indicated by the arrows. Oncepressed to the Yankee dryer 205, the web material 202 is carried on theYankee dryer 205 around the roll to the creping blade 206 which crepesthe traveling web material 202 from the surface of the Yankee dryer 205as indicated at 207. The creped web material 207 exiting from the Yankeedryer 205 then passes over guide and tension rollers 208, 209 and iswound into a soft creped tissue roll 210.

To adhere a partially dried and dewatered paper web material 202 (e.g.,a 10-90 wt. % fiber consistency) entering the Yankee dryer 205 to thesurface of the Yankee dryer 205, a spray boom 211 can be used to apply acreping adhesive composition 218 to the dryer surface 213 which isexposed after the creped tissue web 207 is removed from the dryer 205 toprovide an adhesive dryer surface 214 ahead of the nip between the pressroll 204 and Yankee dryer 205. The spray boom 211 can be a single sprayboom or multi-spray boom, such as a dual-spray boom as illustrated. Thespray boom can include an overspray collection container (not shown).The spray boom 211 is fluidly connected 219 to a mixing pot 215 forfeeding creping adhesive composition from the mixing pot. The mixing pot215 can be equipped with an agitator 217.

The creping adhesive of the present invention can comprise the standardmaterials for creping adhesives such as adhesion glue, creping modifiersand release modifiers. Creping adhesive may also comprise an aqueousstream containing divalent cations that can be introduced into themixing pot 215 in any convenient manner. The resulting creping adhesivecan be pumped or otherwise fed under pressure to the nozzle sprayer(s)of the spray boom 211. To promote drying of the web on the dryer, theYankee dryer 205 can be internally steam heated by conventional or othersuitable arrangements (not shown), externally heated using a hood 212,or using both. This sprayed composition 218 optionally may be applied tothe traveling web 202 directly. However, it may be directly sprayed ontothe dryer surface 213 to limit the pickup of adhesive by the webmaterial 202 and to limit the penetration of adhesive through the webmaterial 202 to the carrying fabric.

Papermaking Materials

The terms “fibrous structure”, “fibrous web”, “web material”, andsimilar terms as used herein refer to a fibrous material that may becomprised of cellulosic and non-cellulosic components. These woodpulp-based cellulosic and non-cellulosic components can includepapermaking fibers and other various additives that are mixed with waterto form an aqueous slurry. This aqueous slurry constitutes the aqueouspapermaking furnish. It is anticipated that wood pulp in all itsvarieties will normally comprise the papermaking fibers. However, othercellulose fibrous pulps, such as cotton linters, bagasse, rayon, etc.,can be used and none are disclaimed. Wood pulps can also includechemical pulps such as, sulfite and sulfate (sometimes called Kraft)pulps as well as mechanical pulps including for example, groundwood,thermomechanical pulp (TMP) and chemithermomechanical pulp (CTMP).

Both hardwood pulps and softwood pulps as well as combinations of thetwo may be employed as papermaking fibers. The term “hardwood pulps” asused herein refers to fibrous pulp derived from the woody substance ofdeciduous trees (angiosperms), whereas “softwood pulps” are fibrouspulps derived from the woody substance of coniferous trees(gymnosperms). Pulps from both deciduous and coniferous trees can beused. Blends of hardwood Kraft pulps, especially eucalyptus, andnorthern softwood Kraft (NSK) pulps are particularly suitable for makingthe tissue webs of the present invention. One of skill in the art willrecognize that layered tissue webs that form tissue and towel productscan utilize hardwood pulps such as eucalyptus for outer layer(s) andnorthern softwood Kraft pulps for the inner layer(s).

Other additives can be added to an aqueous papermaking furnish or thefibrous structure to impart characteristics to the resulting paperproduct or improve the papermaking process. This can include theaddition of a cationic strengthening polymer to the papermaking furnish.Generally, cationic strengthening polymers may be applied in variousamounts, depending on the desired characteristics of the resulting webmaterial. For instance, total wet strength agents between about 0.5 to50 kg/T can be added. These strength polymers can be incorporated intoany layer of a multi-layer tissue web. A cationic strengthening polymercan be a cationic water-soluble resin such as polyamide epichlorohydrin(PAE), urea-formaldehyde resins, melamine formaldehyde resins,polyacrylamide resins, dialdehyde starches, and mixtures thereof.

A “wet strength agent” is a material that when added to pulp fibersprovides a resulting web material with a wet geometric tensile strengthto dry geometric tensile strength ratio in excess of about 0.1.Typically, these are termed either “permanent” wet strength or“temporary” wet strength agents. Such temporary and permanent wetstrength agents may also sometimes function as dry strength agents toenhance the final tissue and/or towel product strength when dry.

The strength additive may be selected from the group consisting ofpermanent wet strength resins, temporary wet strength resins, drystrength additives, and mixtures thereof. If permanent wet strengthresins include polyamide epichlorohydrin, polyacrylamides, insolubilizedpolyvinyl alcohol, urea formaldehyde, polyethyleneimine, and chitosanpolymers. If temporary wet strength is desired, a suitable additive canbe a cationic dialdehyde starch-based resin and dialdehyde starch, andmodified polyacrylamide resins. If dry strength is desired, a suitableadditive can be a polyacrylamide, starch (such as corn starch or potatostarch), polyvinyl alcohol (guar or locust bean gums), and/orcarboxymethyl cellulose.

These wet and dry strength resins may be added to the pulp furnish inaddition to being added by the process described in this disclosure. Itis to be understood that the addition of chemical compounds such as thewet strength and temporary wet strength resins discussed above to thepulp furnish is optional and is not necessary for the practice of thepresent development.

Papermaking Pulp Fiber Chemistry

It has been discovered that a wood pulp (chemical or mechanical) with amolar ratio higher than 10 of the molar amount of monovalent ions to themolar amount of divalent ions (by way of non-limitingexample—[Na⁺]/[Ca⁺²], [Na⁺]/[Mg⁺²], [Na⁺]/[Ca⁺²+Mg⁺²], or represented ingeneral as [Na⁺]/[X⁺²] where X is sum of all divalent ions) hasdifficulty running on tissue/towel/paper machines due to an observedlower pH, negative interactions with tissue/towel Yankee crepingadhesive reliability and tack, and interferes with fiber-to-fiberbonding. Furthermore, it has also been discovered that the papermakingwhite water system with a molar ratio of monovalent to divalent ionsgreater than or equal 50 will also present similar difficulties.

As would be understood by one of skill in the art, a “molar ratio” isdefined as the ratio of the amount of moles of a given substance orelement in a compound (solid, liquid, and/or gas) by the amount of molesof a second given substance or element in the same compound. For theinstant description the molar ratio is the ratio of the amount ofmonovalent ions to the amount of divalent ions. In this example, theamount of moles of monovalent ions (e.g., typically Na⁺) to the amountof moles of divalent ions (e.g., typically Ca⁺²) can be determined bythe molar content of such ions present in papermaking raw fibrous pulp,paper stock, web material or process water and/or filtrates.

Those skilled in the art understand that a tissue and/or towelpapermaking process is a highly complex operation. This highly complexoperation can be significantly effected by minute changes in the pulpraw materials used to supply the papermaking fibers and/or any changesin the water quality used in the entirety of the papermaking process(for example pH). This necessarily includes the papermaking fibers andwater that are fed to any re-pulpers and then ultimately to the papermachine. Impacts on the paper machine caused by these raw materialchanges (e.g., water and/or pulp) can have a drastic impact on thefinally produced web product and can be manifest to virtually alldifferent areas of the paper machine. For example, final web materialproduct defects and the causation can include but not be limited to anincreased number of holes in the finally produced tissue and/or towelfibrous web that is caused by buildup of sticky material on the crepingblade or seal rolls throughout the papermaking process.

This raw material variability can require an increase in creping bladechanges required to keep any final web material product parameterswithin specification. Further, raw material variability can cause anincrease in the thickness, and a change in the material hardness of, theYankee creping adhesive resulting in a required increase of cleaningblade changes, increased creping blade changes, increased tissue sheetstrength variability, increased variability of creping on sheetproperties, and/or increased sheet breaks. Additionally, one of skill inthe art will readily recognize that material variability can also resultin a change in the Yankee creping adhesive coating glass transitionproperties that can result in poor sheet tack (i.e., either too weak ortoo strong making it difficult to crepe) to the Yankee drier, anoticeable sticky material buildup on seal rolls associated with thethrough air drying process, a sticky material buildup on piping andchests that can be released as a result of a pH change of 1 or moreunits, and/or a step-change in water temperature or other system shockor high shear. Surprisingly, it was discovered that these issues wererelated to the molar ratio of monovalent inorganic ionizable cationspecies to divalent ionizable cation species discussed herein in detail.

Furthermore it was surprisingly discovered that a molar ratio ofmonovalent inorganic ionizable cation species (e.g., Lithium (Li⁺),sodium (Na⁺), Potassium (K⁺) and Rubidium (Rb⁺), counter ions, sourcesalts, oxides, derivatives, and combinations thereof) to divalentinorganic ionizable cation species (e.g., beryllium (Be⁺²), magnesium(Mg⁺²), calcium (Ca⁺²), strontium (Sr⁺²), barium (Ba⁺²), radium (Ra⁺²),counter ions, source salts, oxides, derivatives, and combinationsthereof) of higher than about 10 creates the observed difficulties withthe Yankee dryer creping process and the observed defects in theresulting creped web material. Also, it was surprisingly discovered thata molar ratio of monovalent to divalent ions of lower than about 0.1similarly creates these observed difficulties with the Yankee dryercreping process and the observed defects in the resulting creped webmaterial. In this regard, it was found that the addition or thereduction of monovalent and/or divalent ionizable compounds within thepulp manufacturing process or within the papermaking process (i.e., tothe papermaking machine) to maintain a molar ratio of monovalent ions todivalent ions in the solid phase of the incoming structure to the Yankeedrier of about less than or equal to 10 and greater than about 0.1 canreduce these observed negative attributes of the web material removedfrom the surface of the Yankee dryer. One skilled in the art wouldappreciate that the molar ratio of monovalent to divalent ions can beless than or equal to 10, or can range from about 0.1 to about 10, orfrom about 1 to about 9, or about 2 to about 7, or from about 4 to about6, or be about 5.

It has been surprisingly found that the modification of the monovalention to divalent ion molar ratio can be accomplished by adding divalentinorganic ionizable cationic species or removing monovalent inorganicionizable cationic species (also called “MIICS” herein) within thepapermaking process to drive the monovalent to divalent molar ratio toless than or equal to 10. Further, adding divalent inorganic ionizablecationic species (also called “DIICS” herein) or removing MIICS canoccur in the pulp making operation to drive the monovalent to divalentmolar ratio to less than or equal to 10. Also, the addition of DIICS orremoval of MIICS can occur in the pulp bleaching process section as wellas the brown stock washing process section to drive the monovalent todivalent molar ratio to less than or equal to 10. Finally, one of skillin the art will recognize that adding DIICS or removing MIICS can beaccomplished anywhere in the pulp mill water system (washing watersystem and/or the fresh water feed to the pulping operation) or withinthe papermaking water system so that final pulp fiber ion content andthe ionic molar ratio discussed supra, provide a monovalent to divalentmolar ratio of less than or equal to 10.

As mentioned, the addition of DIICS or the removal MIICS can occur atany point ranging from the production of wood pulp fibers at the pulpmill to the creping blade removing the adhesively connected web materialfrom the surface of the Yankee dryer. The techniques and locationswithin the papermaking process are discussed infra. This includesdiscrete discussion related to the locations and techniques suitable forthe addition of DIICS across the pulp and papermaking processes as wellas the locations and techniques suitable for the removal MIICS acrossthe pulp and papermaking processes.

1. Addition of Divalent Inorganic Ionizable Cationic Species

a. Adding Divalent Inorganic Ionizable Cationic Species to the PulpMaking Process or Pulp Mill

In one example of the processes of the present disclosure is theembodiment where divalent inorganic ionizable cationic species (DIICS)(e.g., Ca⁺²) are added in the pulp production process (Kraft,chemithermomechanical, semi-bleached, thermomechanical, or bio-pulpingprocesses), either in solid state or pre-slurried and pumped. This canbe done preferably but not limited to the last stages in pulp productionprocess such as bleaching, washing and drying operations—tanks, chests,pipelines, pumps or any auxiliary equipment that is part of suchprocesses. It may also be done directly (by incorporating such divalentcations salts and/or oxides) on the pulp sheet (during or after sheetformation, before or after drying) or in the stock flow, or indirectlythrough side streams of water and filtrates (such as recirculating whitewater, fresh water streams, and the like). Other embodiments include theuse of compounds where the divalent cations are coupled with thefollowing anions: acetate, formiate, carbonate, bicarbonate, nitrite,sulphate, chloride, fluoride, bromide, and iodine. The target for theaddition of DIICS is to ensure the ratio of monovalent inorganicionizable cationic species MIICS (e.g., Na⁺) to DIICS (e.g., Ca⁺²) isless than or equal to 10.

To determine the molar ratio of MIICS to DIICS, the pulp productionprocess can incorporate the use of a MIICS measuring device and a DIICSmeasuring device. As the pulp material is manufactured, the molarconcentration of the MIICS can be measured in discrete time periods, oreven continuously, with the MIICS measuring device. Similarly, the molarconcentration of the DIICS can be measured in discrete time periods, oreven continuously, with the DIICS measuring device. Based upon the datacollected by the MIICS and DIICS measuring devices, the molar ratio ofthe measured molar concentration of MIICS to the measured molarconcentration of DIICS can be calculated. This ratio can then becompared to the desired MIICS to DIICS ratio of about less than or equalto 10. If the calculated molar ratio in the web material is greater than10 in the web material, then an amount of DIICS can be added to the pulpmanufacturing process.

Additionally, the ratio of MIICS to DIICS can be determined in the finalpulp material produced by the pulp production process. This can resultin the manufacture of saleable pulp product suitable for use in apapermaking process that results in the beneficial production of webmaterial by the papermaking process that has reduced observed defects asdiscussed supra. Here, the molar ratio of MIICS to DIICS in the finallyproduced pulp product can be determined by a quantitative ashingprocess. The ashed pulp product can then be measured for the respectiveconcentration of MIICS and DIICS. By way of non-limiting example, thefinal pulp product produced by the pulp making process can be ashed byfollowing any of several different standards, namely but not limited to:ISO 1762:2015, ISO/DIS 1762, Tappi T211 om-02, Scan C06, ASTM d586-97,AS/NZ 1301.418, ISO 2144, NBRNM-ISO2144, ABNT NBR 13999:2017, IS 6213(p.VII):2012, among others. The ashed product can then be measured forMIICS and DIICS molar content by a technique that enables thequantitative analysis of ions such as Atomic Absorption Spectroscopy,Ion Chromatography, Inductively Coupled Plasma with Mass Spectroscopy(ICP-MS), Inductively Coupled Plasma with Optical Emission Spectroscopy(ICP-OES), and the like.

Based upon the analysis of the ashed pulp product, the molar ratio ofMIICS to DIICS can then be compared to the desired MIICS to DIICS ratioof about less than or equal to 10. If the calculated molar ratio in theweb material is greater than 10 in the pulp product, then an amount ofDIICS can be added to the pulp manufacturing process.

b. Addition of DIICS to the Pulper

One skilled in the art can contemplate the addition of DIICS directly tothe paper machine thick stock pulp system either in the paper machinestock preparation pulper or into any one of the pulp slurry lines,either in solid form of salts being added in conjunction with water tothe pulper or via a pre-slurried mixture that is pumped and metered intopulp stock lines to obtain the desired ratio of monovalent ions todivalent ions is less than or equal to 10. Furthermore, otherembodiments include the use of compounds where the DIICS are coupledwith anions such as acetate, formiate, carbonate, bicarbonate, nitrite,sulphate, chloride, fluoride, bromide, and iodine. In any regard, thetarget for the addition of divalent ions or removal of monovalent ionsis to ensure the ratio of MIICS to DIICS is less than or equal to 10.

It should be understood by one of skill in the art that the molarcontent of MIICS and DIICS in any portion of a papermaking process (eachdiscussed infra) where the papermaking fibers exist in an aqueous statecan be measured with the use of a MIICS measuring device and a DIICSmeasuring device. As the web material is manufactured by the papermakingmachine, the molar concentration of the MIICS can be measured indiscrete time periods, or even continuously, with the MIICS measuringdevice. Similarly, the molar concentration of the DIICS can be measuredin discrete time periods, or even continuously, with the DIICS measuringdevice. Based upon the data collected by the MIICS and DIICS measuringdevices, the molar ratio of the measured molar concentration of MIICS tothe measured molar concentration of DIICS can be calculated. This ratiocan then be compared to the desired MIICS to DIICS ratio of about lessthan or equal to 10. If the calculated molar ratio in the web materialis greater than 10 in the web material, then an amount of DIICS can beadded to the papermaking process.

c. Adding DIICS to the Thick Stock Feed to the Paper Machine.

A second example of the processes of the present disclosure is theembodiment DIICS are added directly to the paper machine thick stockpulp slurry, either in solid state or pre-slurred and pumped. Otherembodiments can include the use of compounds where the DIICS are coupledwith the following anions: acetate, formiate, carbonate, bicarbonate,nitrite, sulphate, chloride, fluoride, bromide, and iodine. The targetfor the addition of divalent ions is to ensure the ratio of monovalentions to divalent ions in the paper machine thick stock pulp slurry isless than or equal to 10.

As discussed supra, the molar content of MIICS and DIICS in the papermachine thick stock pulp slurry can be measured with the use of a MIICSmeasuring device and a DIICS measuring device. The molar ratio of MIICSto DIICS present in the paper machine thick stock pulp slurry can bedetermined as discussed supra.

d. Adding DIICS to the Papermaking Process

Another example of the processes of the present disclosure provides forthe addition of DIICS to the papermaking fibers present in the tissueand towel papermaking process. Suitable tissue and towel papermakingprocesses can include, but not be limited to, conventional dry crepeprocesses, the Voith® ATMOS® process, the Valmet® NTT® process, theValmet® NTTQRT® process, the Andritz® TEX® process, variousthrough-air-dried process, or any other crepe tissue production processavailable and/or envisioned. It is believed that DIICS can be deliveredat any point within the paper or tissue production process, either insolid state or pre-slurried and pumped to approach flow tanks, pipes,pumps or any other devices before and up to and including the papermachine headbox. Other embodiments can include the use of compoundswhere the DIICS are coupled with the following anions: acetate,formiate, carbonate, bicarbonate, nitrite, sulphate, chloride, fluoride,bromide, and iodine. The target for the addition of DIICS to thepapermaking fibers present in the tissue and towel papermaking processis to ensure the molar ratio of MIICS to DIICS in the papermaking fiberspresent in the tissue and towel papermaking process is less than orequal to 10.

As discussed supra, the molar content of MIICS and DIICS in the aqueouspaper fibers present within the paper machine can be measured with theuse of a MIICS measuring device and a DIICS measuring device. The molarratio of MIICS to DIICS present the aqueous paper fibers present withinthe paper machine can be determined as discussed supra.

e. Papermaking Machine Fresh or Make-Up Water:

Another example of the processes of the present disclosure provides forthe addition of DIICS to the tissue and towel papermaking process viathe papermaking fresh or make-up water system. Adding ionizable cationscan change the character and/or hardness of the paper machine water suchthat it has excess DIICS available to ion exchange with the pulp toachieve the target ratio of MIICS to DIICS of less than or equal to 10.

As discussed supra, the molar content of MIICS and DIICS in thepapermaking fresh or make-up water system can be measured with the useof a MIICS measuring device and a DIICS measuring device. The molarratio of MIICS to DIICS present the papermaking fresh or make-up watersystem can be determined as discussed supra.

One of skill in the art will also recognize that the molar content ofMIICS and DIICS in the water streams can also be determined by aquantitative ashing process such as those described herein) followed byany quantitative analytical technique that enables the quantitativeanalysis of ions such as AA, ICP-MS, IC, ICP-OES, among others (alsodiscussed previously herein).

f. Papermaking Machine White Water

In yet another example of the processes of the present disclosure DIICScan be added indirectly through side streams of water and filtrates(such as recirculating white water, papermaking water treatmentprocesses and shower makeup water sources) used in the tissue or papermachine. It was surprisingly found that the ratio for this method ofapplication of DIICS was different from that observed in pulp additionto affect the same impact on the tissue papermaking creping adhesivesystem reliability. Here, it is preferred that the molar ratio of MIICSto DIICS is less than or equal to 50 versus the pulp target of less thanor equal to 10. The molar ratio of MIICS to DIICS in the water circuitis higher due to differences in mass balance and the ion-exchangereactions taking place with the pulp, as well as to avoid scaling andits undesired side effects in the paper machine.

As discussed supra, the molar content of MIICS and DIICS in thepapermaking machine white water system can be measured with the use of aMIICS measuring device and a DIICS measuring device. The molar ratio ofMIICS to DIICS present the papermaking machine white water system can bedetermined as discussed supra.

One of skill in the art will also recognize that the molar amounts ofMIICS and/or DIICS to be added into the streams may also be estimated bymaterial balance after a preliminary quantitative analysis.

g. Spraying DIICS onto a Surface of the Web Material Prior to Contactwith the Yankee Dryer

In yet another example of the processes of the present disclosureprovides for the addition of DIICS done directly through the applicationof a concentrated mixture of DIICS via a topical application to the webmaterial prior to the web material being pressed to the Yankee dryer forfinal drying and creping. One skilled in the art can envision a spray,weir, roll or other system to apply a metered amount of divalent ions tothe surface of the paper before the sheet contacts with Yankee dryer andcreping adhesive mixture thereby improving the adhesion of the sheet tothe Yankee dryer. The adhesion profile modification can be reachedeither by changes in adherence, durability or thickness of the adhesivechemical layer to the surface of the Yankee dryer by the modificationimparted by the controlled ratio of MIICS to DIICS.

The molar content of MIICS and DIICS present in the web material can bemeasured with any equipment understood and known to those of skill inthe art for measuring the molar content of MIICS and DIICS. The molarratio of MIICS to DIICS present the papermaking machine white watersystem can be determined as discussed supra.

h. Addition of DIICS to the Yankee Creping Adhesive Composition

As indicated, the addition of DIICS to the creping adhesive composition218 may be accomplished by adding soluble salts and/or an aqueous streamcontaining a concentrated mixture of dissolved cations, which can bediluted, such as on site of the creping location in a mix pot or in linewith other materials that are to be sprayed on the cylindrical dryer oreven indirectly to the pre-dried sheet between points 202 and 204 asillustrated in FIG. 2.

For example, DIICS can be either in solid state or pre-slurried andadded in the tissue production process directly into the crepingadhesive composition dilution/make-up tanks. One skilled in the art canenvision altering the ionic character of any component of amulticomponent glue system such that the creping adhesive ensures thatthe interface of the creping adhesive/tissue sheet has a ratio of MIICSto DIICS of less than or equal to 10. Therefore, it is contemplated thatthe desired MIICS to DIICS molar ratio can be accomplished through achange in the make-up solution for the creping adhesive, the crepingadhesive components, or other additive (such as creping or release aids)such that the final creping adhesive mixture has excess ionized DIICSthat are able to modify the Yankee coating performance as provided byany of the known and/or understood ion-exchange models with fibers asthey contact the Yankee dryer surface. Without desiring to be bound bytheory, it is believed that this would mimic the Dreshfield effect thathappens with the ion-exchange pulp but, at this point, the ratio ofMIICS to DIICS is directly introduced at the edge of the sheet and theYankee dryer surface.

The addition of DIICS to the creping adhesive composition 218 mayrequire the installation of a device to spray the divalent ions streamat this point, what is not typically present. With the use of theadhesive formulations of the present invention, a superior balance ofadhesion and release properties of the fiber web from the surface of adryer or TAD fabric can be achieved. Comparable or better tack profilesusing a biodegradable additive at lower use rates of conventionalpolyvinyl alcohol creping adhesives (PVOH) or wet strength resins can beobtained with adhesive formulations of the present invention. Further,the adhesive formulation of the present disclosure can be used in otherapplications of the paper industry or other industries. The adhesiveformulation of the present invention can be considered biodegradable,and/or non-toxic, and/or contains one or more food-grade components. Thetarget for the addition of DIICS is to ensure the ratio of MIICS toDIICS is less than or equal to 10.

The molar content of MIICS and DIICS present in the creping adhesivecomposition 218 can be measured with any equipment understood and knownto those of skill in the art for measuring the molar content of MIICSand DIICS. The molar ratio of MIICS to DIICS present the crepingadhesive composition 218 can be subsequently determined as discussedsupra.

i. Addition of DIICS to the Yankee Creping Adhesive CompositionContinuously to the Yankee Drum or Web Material

The addition of DIICS can be provided directly to the Yankee dryersurface by a dedicated stream of a slurry containing DIICS sprayed ontothe surface of the Yankee dryer by a dedicated spray boom or indirectlyby means of a stream, say spraying, onto the tissue sheet or the fabricsin the tissue machine positioned prior to the Yankee dryer. The targetis to ensure the ratio of MIICS to DIICS is less than or equal to 10.

Alternatively, the addition of DIICS can be provided directly to theYankee dryer surface by a dedicated stream of a slurry containing DIICSby a roll application system to ensure that the presence of ionizabledivalent cationic species of the creping adhesive prior to sheet contactis sufficient to provide a ratio of MIICS to DIICS that is less than orequal to 10.

The molar content of MIICS and DIICS present in the creping adhesivecomposition 218 provided directly to the Yankee dryer surface can bemeasured with any equipment understood and known to those of skill inthe art for measuring the molar content of MIICS and DIICS. The molarratio of MIICS to DIICS present the creping adhesive composition 218directly to the Yankee dryer surface can be subsequently determined asdiscussed supra.

Alternatively, the molar content of MIICS and DIICS present in the webmaterial prior to contact with the Yankee dryer surface can be measuredby an ashing process according to any of ISO 1762:2015, ISO/DIS 1762,Tappi T211 om-02, Scan C06, ASTM d586-97, AS/NZ 1301.418, ISO 2144,NBRNM-ISO2144, ABNT NBR 13999:2017, and IS 6213 (p.VII):2012. The ashedweb material can be measured for the respective concentration of MIICSand DIICS. The ashed web material can then be measured for MIICS andDIICS molar content by a technique that enables the quantitativeanalysis of ions such as Atomic Absorption Spectroscopy, IonChromatography, Inductively Coupled Plasma with Mass Spectroscopy(ICP-MS), Inductively Coupled Plasma with Optical Emission Spectroscopy(ICP-OES), and the like. The molar ratio of MIICS to DIICS present inthe web material being applied to the Yankee dryer surface can besubsequently determined as discussed supra. DIICS can then be provideddirectly to the Yankee dryer surface by a dedicated stream of a slurrycontaining DIICS by any known application system to ensure that thepresence of ionizable divalent cationic species of the creping adhesiveprior to sheet contact is sufficient to provide a ratio of MIICS toDIICS that is less than or equal to 10.

One of skill in the art will also recognize that the MICCS to DICCSmolar ratio can also be adjusted following a material (or molar) balancecalculation and incoming flow balance and sheet or water streamcomposition.

2. Removal of Monovalent Inorganic Ionizable Cationic Species (MIICS)

It has also been surprisingly found that the modification of themonovalent ion to divalent ion molar ratio can be accomplished byremoving MIICS within the pulp making and/or papermaking process todrive the MIICS to DIICS molar ratio to less than or equal to 10. Theremoval of MIICS can occur at any point ranging from the production ofthe wood pulp fibers to form the raw pulp material for a papermakingprocess at the pulp mill through the wet-end of the papermaking process.The techniques and locations within the entirety of the pulp andpapermaking processes are discussed infra. This includes discussionsrelated to the discrete locations and techniques suitable for theremoval MIICS across the entire pulp and papermaking processes.

a. Reverse Osmosis

A reverse osmosis process suitable for use with the present disclosurewill push water through a membrane with a high-pressure pump to remove acontaminant (here the contaminant is MIICS). Here, the removal of MIICSfrom any pulp or papermaking process water can be suitably provided at alevel to drive the MIICS to DIICS molar ratio to less than or equal to50. In the present system, the amount of pressure to force water acrossthe semi-permeable membrane in a reverse osmosis system will depend onhow saturated the feed water is with MIICS. The higher the MIICSconcentration, the more pressure will be needed to overcome the naturalosmotic pressure. When adequate pressure is applied, water molecules canpass through the reverse osmosis membrane and the contaminants (i.e.,MIICS) can be discharged. The contaminated water containing MIICS canthen be drained away or used as feed water and passed through thereverse osmosis system again for further cleansing.

In accordance with the present disclosure, a reverse osmosis system canbe installed to remove excess MIICS from any of the water recoveryprocess related to pulp making and/or from the paper machine whitewater. A reverse osmosis system suitable for the removal of MIICS can behighly desirable for use with paper machines that utilize a partially oreven a highly closed water loop system. In any regard, the set-point ofMIICS removal is positioned to drive the MIICS to DIICS molar ratio toless than or equal to 50 for the relevant water stream.

b. Distillation

A distillation process suitable for use with the present disclosure canutilize temperature changes to evaporate and re-condense water from arecovery process related to pulp making and/or from the paper machinewhite water. It has been surprisingly found that inorganic minerals suchas MIMICS do not usually transfer into the condensed water. The removalof MIICS from the respective process water is provided at a suitablelevel to drive the MIICS to DIICS molar ratio to less than or equal to50.

By way of non-limiting example, a distillation column system can beinstalled to purify the water in a closed water loop of a paper machine.It was found that this distillation process can remarkably reduce theamount of dissolved MIICS present within the water loop. As the watersteam in the distillation column condenses with virtually noconcentration of MIICS disposed therein, one of skill in the art couldthen also add DIICS in order to provide a MIICS to DIICS molar ratio thetreated process water of less than or equal to 50.

c. Ion Exchange—Substitution of DIICS by MIICS and/or Substitution ofMIICS by DIICS.

Molecular sieves can be either natural or synthetic materials withregular and uniform pore sizes and a high surface area and having aninternal channel structure that is capable of separating molecules ofdifferent dimensions. By way of example, zeolites are a class ofmolecular sieves that have a crystalline structure composed ofaluminosilicate (occasionally doped with other metals). This structureprovides cavities that can be occupied by large cations and watermolecules thereby presenting high adsorption capacity. Molecular sievescan be used as catalysts (directly or as support for catalysts),adsorbents, and/or ion-exchange resins. The incorporation of aluminum inthe silicate structure can result in an anionic character that can beneutralized by cations such as calcium, sodium or potassium.

It is well understood by those skilled in the art of physical chemistry,inorganic chemistry, and/or materials science that molecular sieves canbe used to soften hard water. This is achieved by means of using a MIICSform of molecular sieve in a DIICS-rich water environment. Here, themolecular sieve can trap MIICS and release DIICS to the water, resultingin a decreased hardness level. The removal of MIICS from process watercan be provided at a suitable level to drive the MIICS to DIICS molarratio to less than or equal to 50.

Not being bound to the theory, we envision that the present disclosurecan make use of molecular sieves to selectively increase theconcentration of DIICS, or MIICS, in such a way that the required molarratio of MIICS to DIICS of less than or equal to 50 in the liquid phaseor less than 10 in the fibrous (i.e., solid) phase of the pulp and/orpapermaking process is met. In any regard, as discussed supra, theaddition of DIICS and/or the trapping/removal of MIICS anywhere in thepulp and/or papermaking process by means of such an ion exchange canimprove the performance from a non-treated state.

For example, a treatment can be accomplished by direct addition of DIICSto achieve a molar ratio of MIICS to DIISC less than or equal to 10 inthe fibrous web at the Yankee dryer, or by indirect treatment of thewater in the paper machine so that the ratio of MIICS to DIICS in waterwould be less than or equal to 50. Molecular sieves can be used toremove specifically some of the MIICS, by donation of monovalent ions tothe system, say, at the recirculating white water circuit in a papermachine.

d. Other Means to Selectively Add and/or Remove MIICS and/or DIICS

Not being bound to the theory, it is believed that advances inflocculation and precipitation chemistry can also control the amount ofDIICS and/or MIICS in either the solid or liquid phases describedherein. It is believed that these processes can accomplish ionic controleither by in situ release or removal in the web substrate productionprocess or water streams of MIICS and/or DIICS. Further, it is believedthat nanofiltration technology can also control the amount of DIICSand/or MIICS in either of the solid or liquid phases described in thisinvention. It is believed that a nanofiltration process can accomplishionic control either by in situ release or removal in the paperproduction process or water streams of MIICS and/or DIICS.

Not being bound to theory, it is believed that advances in other waterdesalination processes (like the distillation and reverse osmosisalready detailed herein) can be considered as ways to remove MIICSand/or DIICS in water streams. Suitable desalination processes conclude,but not be strictly limited to, vacuum distillation, multi-stage flashdistillation, multiple-effect distillation, freeze-thaw, solarevaporation, membrane distillation, and combinations thereof.

Not being bound to theory, it is envisioned that advances in variouschelating chemistry processes can be used to remove MIICS and/or DIICSto soften water in fluid streams in the paper machine. These chelatingprocesses can be used in either water or slurry phases and can be basedupon non-limiting chelating agents such as citric acid, EDTA, DTPA,sodium phytate/phytic acid, tetrasodium glutamate diacetate, trisodiumethylenediamine disuccinate, and combinations thereof.

Not being bound to theory, we also envision the removal of hardness ionspresent in water streams by precipitation following the Clark's process.This process provides lime in the form of limewater added to raw water,raising the pH, and shifting the equilibrium of the carbonate species inthe water. Dissolved carbon dioxide (CO₂) is changed into bicarbonate(HCO₃ ⁻) and then carbonate (CO₃ ⁻²). This action causes calciumcarbonate to precipitate due to exceeding the solubility product.Additionally, magnesium can be precipitated as magnesium hydroxide in adouble displacement reaction. Both calcium and magnesium ions in the rawwater and calcium added in the form of lime are precipitated.

3. Feed Forward Control

The present disclosure also provides for the control of the addition ofDIICS accomplished via the utilization of feed forward control wherebythe papermaking white water and/or the papermaking pulp streams aremonitored to determine the ratio of MIICS to DIICS. If the ratio ofMIICS to DIICS is greater than 10, a feed forward control loop couldtrigger the addition of DIICS (or removal of MIICS as aforementioned)either to the web material immediately before the Yankee dryer, to thecreping adhesive make-up system, to the Yankee dryer surface directly,or by any other means envisioned by one skilled in the art, such thatthe web material that bonds to the Yankee dryer has a ratio MIICS toDIICS of less than or equal to 10. It is believed that the describedon-line control process will recognize that all pulps developed forvarious papermaking processes are different. Therefore, the describedon-line control process provides a clear solution to run all pulps atthe same reliability on any paper machine.

The control system contemplated utilizes non-destructive ion-selectiveelectrode probes to measure the quantity of mono and divalent ions in atissue machine stock of any particular unit operation of the papermakingmachine having a fluidized phase (i.e., the papermaking fibers areprovided in and aqueous environment). For example, the papermakingmachine can be provided with a monovalent inorganic ionizable cationspecies (MIICS) measuring device and a divalent inorganic ionizablecation species (DIICS) measuring device. As the web material ismanufactured by the papermaking machine, the molar concentration of theMIICS in can be measured, in discrete time periods or even continuouslywith the MIICS measuring device. Additionally, the molar concentrationof the DIICS can be measured, in discrete time periods or evencontinuously with the DIICS measuring device. Based upon the datacollected by the MIICS measuring device and the DIICS measuring devicethe molar ratio of the measured molar concentration of the MIICS to themeasured molar concentration of the DIICS can be calculated and comparedto the desired MIICS to DIICS molar ratio of about less than or equal to10. If the calculated molar ratio of MIICS to DIICS in the web materialis greater than 10 in the web material in any of the stock chest, headbox, forming surface, and/or any drying surface, then an amount of DIICScan be added to the papermaking machine.

Similarly, if the data from the papermaking machine water system streamsis then coupled with machine throughput data to calculate the additionof divalent ions to reach the desired less than or equal to 50 molarratio of MIICS to DIICS in these streams. A second control systemcontemplated utilizes ion selective electrode probes to measure thequantity of MIICS to DIICS in the tissue white water system. This datais then coupled with machine throughput data to calculate the additionof DIICS to reach the desired less than or equal to 50 molar ratio ofMIICS to DIICS in the white water. As required, an amount of DIICS canbe added to the papermaking machine to obtain the requisite molar ratioof MIICS to DIICS.

Those skilled in the art of papermaking can determine multiple dosinglocations throughout the paper machine at all the papermaking machineunit operations to include, but not be limited to, the paper machinewhite water return loop, the papermaking pulpers, the paper machinestock chests or dilution water streams feeding these chests, the papermachine mix chests, the paper machine head box and it is contemplatedthe ions being added via spray booms on the wet and/or dry end.Surprisingly, it was discovered that the DIICS aqueous stream is equallyeffective when coupled with the Yankee creping adhesive spray, Yankeecreping adhesive make-up water or via a separate spray boom inconjunction with the Yankee creping adhesive addition.

Additionally, an off-line signal can also be provided to the controlsystem by means of ashing down the papermaking pulp and/or the webmaterial and further measuring the concentration of ionic components(i.e., MIICS and DIICS). By way of non-limiting example, the final pulpproduct produced by the pulp making process (e.g., the pulp bale, driedproduct, dried pulp sheets, and/or any intermediate processes) and/orthe web material can be ashed by following any of several differentstandards, namely but not limited to: ISO 1762:2015, ISO/DIS 1762, TappiT211 om-02, Scan C06, ASTM d586-97, AS/NZ 1301.418, ISO 2144,NBRNM-ISO2144, ABNT NBR 13999:2017, IS 6213 (p.VII):2012, among others.The ashed product can then be measured for MIICS and DIICS molar contentby a technique that enables the quantitative analysis of ions such asAtomic Absorption Spectroscopy, Ion Chromatography, Inductively CoupledPlasma with Mass Spectroscopy (ICP-MS), Inductively Coupled Plasma withOptical Emission Spectroscopy (ICP-OES), and the like. Based upon theanalysis, an amount of DIICS can be added to the pulp manufacturingprocess and/or the papermaking machine to obtain the requisite molarratio of MIICS to DIICS (i.e., a molar ratio of MIICS to DIICS of lessthan or equal to 10).

4. Feed Back Control

In addition to the previously described feed-forward system, it isenvisioned that a feed-back control system can also be utilized tomaintain the requisite molar ratio of MIICS to DIICS. Surprisingly itwas discovered that the amount of holes present in the web materialafter the creping process can be readily reduced with the ionic controltechniques described herein.

By way of non-limiting example, an on-line sheet defect measuringscanner can be used to detect the amount of holes present in the webmaterial. Alternatively, the control system could utilize ion-selectiveelectrode probes to measure the quantity of mono and divalent ions in atissue machine stock. For example, the papermaking machine can beprovided with a monovalent inorganic ionizable cation species (MIICS)measuring device and a divalent inorganic ionizable cation species(DIICS) measuring device.

As the web material is manufactured by the papermaking machine, themolar concentration of the MIICS and DIICS in can be measured, indiscrete time periods or even continuously with the respective MIICS andDIICS measuring devices. Additionally, the molar concentration of theDIICS in can be measured, in discrete time periods or even continuouslywith the DIICS measuring device.

This data can be coupled with the ion selective electrode probes(described supra) to measure the quantity of MIICS to DIICS in thepapermaking white water system. This forms the feed-back control loop ofthe paper machine. The feed-back control circuitry provided with thepaper machine can provide a signal to increase or decrease the molarratio of MIICS to DIICS by means of increasing or reducing the add-onmolar ratio of MIICS or DIICS to meet the required MIICS to DIICS molarratio of about or less than or equal to 10 in the web material or ofabout or less than or equal to 50 in the water streams. This signalprovided by the feed-back control circuitry can be sent to any of themultiple dosing locations throughout the paper machine at all thepapermaking machine unit operations to include, but not be limited tothe paper machine white water return loop, papermaking pulpers, papermachine stock chests or dilution water streams feeding these chests,paper machine mix chests, paper machine head box. It is believed thatthe relevant ionic mixture can be added via spray booms on the wetand/or dry end of the paper machine. Those skilled in the art ofpapermaking may recognize the use of such a spray boom located on thewet and/or dry end of the paper machine can necessarily provide for apoint of easier control and quicker response in order to provide aresulting molar ratio of MIICS to DIICS of about less than or equal to10 in the solid phase web material evoluting from the paper machine.

An off-line signal can also be provided to the control system by meansof ashing down the pulp material and/or web material and furthermeasuring the molar concentration of ionic components (i.e., MIICS andDIICS) therein. By way of non-limiting example, the final pulp productproduced by the pulp making process (e.g., the pulp bale, dried product,dried pulp sheets, and/or any intermediate processes) and/or the webmaterial can be ashed by following any of several different standards,namely but not limited to: ISO 1762:2015, ISO/DIS 1762, Tappi T211om-02, Scan C06, ASTM d586-97, AS/NZ 1301.418, ISO 2144, NBRNM-ISO2144,ABNT NBR 13999:2017, IS 6213 (p.VII):2012, among others. The ashedproduct can then be measured for MIICS and DIICS molar content by atechnique that enables the quantitative analysis of ions such as AtomicAbsorption Spectroscopy, Ion Chromatography, Inductively Coupled Plasmawith Mass Spectroscopy (ICP-MS), Inductively Coupled Plasma with OpticalEmission Spectroscopy (ICP-OES), and the like.

The control system herewith described applies equally to a paper machineor a pulp dryer machine to keep desired or specified amount of ions inthe pulp as described in this invention, no matter how the addition orremoval of the indicated ions is performed.

Similarly, it is believed that an imaging device can be used to obtaindigital images of the web material surface in production to measure thecrepe of a moving web material as a basis for feed-back inducedcorrective actions to implement proper ionic balance as a response tochanges in crepe structure. For example, one of skill in the art willrecognize that imaging devices can embody methods and apparatii tomonitor and control the characteristics of the Yankee dryer crepingprocess by means of optical properties of various points along a crepedweb material and converting such measurements into defining data. Thisdata can then be fed to the appropriate portion of the papermakingprocess equipment. It was found that this process can result in a markedincrease in quality and efficiency in papermaking.

The present disclosure can also make use of similar imaging devices toprovide an input signal to generate an output correction signal toincrease or decrease the molar ratio of MIICS to DIICS. This process canbe an effective manner to increase or reduce the add-on molar ratio ofMIICS or DIICS to meet the required MIICS to DIICS molar ratio of aboutless than or equal to 10 in the web material or of about less than orequal to 50 in the water streams.

It should be understood that the output correction signal created bythis described feed-back system can be sent to any of the multipledosing locations throughout the paper machine at all the papermakingmachine unit operations to include, but not be limited to, the papermachine white water return loop, papermaking pulpers, paper machinestock chests or dilution water streams feeding these chests, papermachine mix chests, paper machine head box. Further, it is contemplatedthe MIICS and/or DIICS being added to the particular dosing location canbe provided via spray booms on the wet and/or dry end of the papermakingmachine.

In yet another non-limiting embodiment, an imaging device used to obtaindigital images of the web material surface can be used to collecttopographic three-dimensional information of the web material sheet thatcan be used to control softness of the resulting tissue and/or towelsheet. This topographic three-dimensional information of the webmaterial sheet can be used as a basis for corrective actions toimplement as response to changes in web material structure.

It is also believed in another non-limiting embodiment that an imagingdevice used to obtain digital images of the web material surface can beused to collect topographic three-dimensional information of the webmaterial can be used as an input signal to generate an output correctionsignal. This output correction signal can then be used by controlcircuitry known by those of skill in the art to increase or decrease themolar ratio of MIICS to DIICS by increasing or reducing the add-on molarratio of MIICS to DIICS to meet the required molar ratio of about lessthan or equal to 10 in the web material or of about less than or equalto 50 in the relevant papermaking water streams. It should be understoodthat the output correction signal created by this described feed-backsystem can be sent to any of the multiple dosing locations throughoutthe paper machine at all the papermaking machine unit operations toinclude, but not be limited to, the paper machine white water returnloop, papermaking pulpers, paper machine stock chests or dilution waterstreams feeding these chests, paper machine mix chests, paper machinehead box. Further, it is contemplated the MICCS and/or DIICS being addedto the particular dosing location can be provided via spray booms on thewet and/or dry end of the papermaking machine.

Any dimensions and/or values disclosed herein are not to be understoodas being strictly limited to the exact numerical values recited.Instead, unless otherwise specified, each such dimension and/or value isintended to mean both the recited dimension and/or value and afunctionally equivalent range surrounding that dimension and/or value.For example, a dimension disclosed as “40 mm” is intended to mean “about40 mm.”

Every document cited herein, including any cross referenced or relatedpatent or application and any patent application or patent to which thisapplication claims priority or benefit thereof, is hereby incorporatedherein by reference in its entirety unless expressly excluded orotherwise limited. The citation of any document is not an admission thatit is prior art with respect to any invention disclosed or claimedherein or that it alone, or in any combination with any other referenceor references, teaches, suggests or discloses any such invention.Further, to the extent that any meaning or definition of a term in thisdocument conflicts with any meaning or definition of the same term in adocument incorporated by reference, the meaning or definition assignedto that term in this document shall govern.

While particular embodiments of the present invention have beenillustrated and described, it would be obvious to those skilled in theart that various other changes and modifications can be made withoutdeparting from the spirit and scope of the invention. It is thereforeintended to cover in the appended claims all such changes andmodifications that are within the scope of this invention.

What is claimed is:
 1. A process for manufacturing a creped web materialon a papermaking machine having a Yankee drum drying system, whereinsaid process comprises the steps of: a) producing said web material withsaid papermaking machine; b) measuring a molar amount of a monovalentinorganic ionizable cation species (MIICS) in said web material; c)measuring a molar amount of a divalent inorganic ionizable cationspecies (DIICS) in said web material; d) calculating a molar ratio ofsaid measured molar amount of said MIICS to said measured molar amountof said DIICS in said web material; e) determining if said molar ratioof MIICS to DIICS is about less than or equal to 10; and, f) if saidmolar ratio of MIICS to DIICS is greater than about 10, adding an amountof DIICS to said papermaking machine to adjust said molar ratio of MIICSto DIICS so said web material adhering to said Yankee drum drying systemhas a molar ratio of MIICS to DIICS of about less than or equal to 10.2. The process of claim 1 wherein said step d) further comprises thestep of adding an amount of DIICS to said papermaking machine to adjustsaid molar ratio of MIICS to DIICS so said web material adhering to saidYankee drum drying system has a molar ratio of MIICS to DIICS rangingfrom about 0.1 to about
 10. 3. The process of claim 2 wherein said stepd) further comprises the step of adding an amount of DIICS to saidpapermaking machine to adjust said molar ratio of MIICS to DIICS so saidweb material adhering to said Yankee drum drying system has a molarratio of MIICS to DIICS ranging from about 2 to about
 7. 4. The processof claim 2 wherein said step d) further comprises the step of adding anamount of DIICS to said papermaking machine to adjust said molar ratioof MIICS to DIICS so said web material adhering to said Yankee drumdrying system has a molar ratio of MIICS to DIICS ranging from about 4to about
 6. 5. The process of claim 1 wherein said MIICS is selectedfrom the group consisting of Li⁺, Na⁺, K⁺, Rb⁺, counter ions, sourcesalts, oxides, derivatives, and combinations thereof and said DIICS isselected from the group consisting of Be⁺², Mg⁺², Ca⁺², Sr⁺², Ba⁺²,Ra⁺², counter ions, source salts, oxides, derivatives, and combinationsthereof.
 6. The process of claim 5 wherein said MIICS is Na⁺ and saidDIICS is Ca⁺².
 7. The process of claim 1 wherein said process furthercomprises the step of, prior to step a), supplying said papermakingmachine with one or more fibers.
 8. The process of claim 7 furthercomprising the step of modifying said one or more fiber before deliveryto said papermaking machine by the addition of DIICS at a level thatprovides the molar ratio of has a molar ratio as measured in the solidphase of MIICS to DIICS of about less than or equal to
 10. 9. Theprocess of claim 8 wherein said process further comprises the step ofmanufacturing said one or more fibers with a pulp making process, saidpulp making process having a process selected from the group consistingof a pulping process, a bleaching process, and a drying process.
 10. Theprocess of claim 9 wherein said process further comprises the step ofadding said DIICS to at least one of said pulping process, saidbleaching process, or said drying process at a level that provides themolar ratio of has a molar ratio as measured in the solid phase of MIICSto DIICS of about less than or equal to
 10. 11. The process of claim 1wherein said process further comprises the step of, prior to step a),providing said papermaking machine with a wet structure formationsection, and said step d) further comprises the step of adding saidamount of DIICS to said wet structure formation section.
 12. The processof claim 1 wherein said process further comprises the step of, prior tostep a), providing said papermaking machine with a headbox wetingredient mixing system and said step d) further comprises the step ofadding said amount of DIICS to said headbox wet ingredient mixingsystem.
 13. A process for manufacturing a creped web material on apapermaking machine having a Yankee drum drying system, wherein saidprocess comprises the steps of: a) producing said web material with saidpapermaking machine; b) measuring a molar amount of a monovalentinorganic ionizable cation species (MIICS) in said web material; c)measuring a molar amount of a divalent inorganic ionizable cationspecies (DIICS) in said web material; d) calculating a molar ratio ofsaid measured molar amount of said MIICS to said measured molar amountof said DIICS in said web material; e) determining if said molar ratioof MIICS to DIICS is about less than or equal to 10; and, f) if saidmolar ratio of MIICS to DIICS is greater than about 10, applying anamount of DIICS to a surface of said Yankee drum drying system to adjustsaid molar ratio of MIICS to DIICS so said web material adhering to saidYankee drum drying system has a molar ratio of MIICS to DIICS of aboutless than or equal to
 10. 14. The process of claim 13 wherein said MIICSis selected from the group consisting of Li⁺, Na⁺, K⁺, Rb⁺, counterions, source salts, oxides, derivatives, and combinations thereof andsaid DIICS is selected from the group consisting of Be⁺², Mg⁺², Ca⁺²,Sr⁺², Ba⁺², Ra⁺², counter ions, source salts, oxides, derivatives, andcombinations thereof.
 15. The process of claim 14 wherein said MIICS isNa⁺ and said DIICS is Ca⁺².
 16. The process of claim 14 wherein saidMIICS is Na⁺ and said DIICS is Ca⁺².
 17. The process of claim 13 whereinsaid MIICS is selected from the group consisting of Li⁺, Na⁺, K⁺, Rb⁺,counter ions, source salts, oxides, derivatives, and combinationsthereof and said DIICS is selected from the group consisting of Be⁺²,Mg⁺², Ca⁺², Sr⁺², Ba⁺², Ra⁺², counter ions, source salts, oxides,derivatives, and combinations thereof.
 18. A process for manufacturing acreped web material on a papermaking machine having a Yankee drum dryingsystem, wherein said process comprises the steps of: a) providing saidpapermaking machine with a white water loop section, said white waterloop section providing said papermaking machine with an aqueous stream;b) producing said web material with said papermaking machine; c)measuring a molar amount of a monovalent inorganic ionizable cationspecies (MIICS) in said web material; d) measuring a molar amount of adivalent inorganic ionizable cation species (DIICS) in said webmaterial; e) calculating a molar ratio of said measured molar amount ofsaid MIICS to said measured molar amount of said DIICS in said webmaterial; f) determining if said molar ratio of MIICS to DIICS is aboutless than or equal to 10; and, g) if said molar ratio of MIICS to DIICSis greater than about 10, adding an amount of DIICS to said white waterloop section of said papermaking machine to adjust said molar ratio ofMIICS to DIICS in said aqueous stream to about less than or equal to 50.19. The process of claim 18 wherein said MIICS is selected from thegroup consisting of Li⁺, Na⁺, K⁺, Rb⁺, counter ions, source salts,oxides, derivatives, and combinations thereof and said DIICS is selectedfrom the group consisting of Be⁺², Mg⁺², Ca⁺², Sr⁺², Ba⁺², Ra⁺², counterions, source salts, oxides, derivatives, and combinations thereof. 20.The process of claim 19 wherein said MIICS is Na⁺ and said DIICS isCa⁺².
 21. A process for manufacturing a creped web material on apapermaking machine having a Yankee drum drying system, wherein saidprocess comprises the steps of: a) providing said papermaking machinewith a fresh water makeup system, said fresh water makeup systemproviding said papermaking machine with an aqueous stream; b) producingsaid web material with said papermaking machine; c) measuring a molaramount of a monovalent inorganic ionizable cation species (MIICS) insaid web material; d) measuring a molar amount of a divalent inorganicionizable cation species (DIICS) in said web material; e) calculating amolar ratio of said measured molar amount of said MIICS to said measuredmolar amount of said DIICS in said web material; f) determining if saidmolar ratio of MIICS to DIICS in said web material is about less than orequal to 10; and, g) if said molar ratio of MIICS to DIICS is greaterthan about 10, adding an amount of DIICS to said fresh water makeupsystem of said papermaking machine to adjust a molar ratio of MIICS toDIICS in said aqueous stream to less than or equal to
 50. 22. Theprocess of claim 21 wherein said MIICS is selected from the groupconsisting of Li⁺, Na⁺, K⁺, Rb⁺, counter ions, source salts, oxides,derivatives, and combinations thereof and said DIICS is selected fromthe group consisting of Be⁺², Mg⁺², Ca⁺², Sr⁺², Ba⁺², Ra⁺², counterions, source salts, oxides, derivatives, and combinations thereof. 23.The process of claim 22 wherein said MIICS is Na⁺ and said DIICS is Ca′.24. A process for manufacturing a creped web material on a papermakingmachine having a Yankee drum drying system, wherein said processcomprises the steps of: a) supplying said Yankee drum drying system witha creping adhesive; b) applying said creping adhesive to a surface ofsaid Yankee drum drying system; c) producing said web material with saidpapermaking machine; d) measuring a molar amount of a monovalentinorganic ionizable cation species (MIICS) in said web material; e)measuring a molar amount of a divalent inorganic ionizable cationspecies (DIICS) in said web material; f) calculating a molar ratio ofsaid measured molar amount of said MIICS to said measured molar amountof said DIICS in said web material; g) determining if said molar ratioof MIICS to DIICS is about less than or equal to 10; and, h) if saidmolar ratio of MIICS to DIICS is greater than about 10, adding an amountof DIICS to said creping adhesive so that said web material upon contactwith said creping adhesive disposed upon said surface of said Yankeedrum drying system DIICS has a molar ratio of MIICS to DIICS of aboutless than or equal to
 10. 25. The process of claim 24 wherein said MIICSis selected from the group consisting of Li⁺, Na⁺, K⁺, Rb⁺, counterions, source salts, oxides, derivatives, and combinations thereof andsaid DIICS is selected from the group consisting of Be⁺², Mg⁺², Ca⁺²,Sr⁺², Ba⁺², Ra⁺², counter ions, source salts, oxides, derivatives, andcombinations thereof.
 26. The process of claim 25 wherein said MIICS isNa⁺ and said DIICS is Ca⁺².
 27. The process of claim 24 furthercomprising the step of providing said creping adhesive with at least onecompound selected from the group consisting of adhesive compounds,creping aids, release aids, creping adhesive glass transition pointmodifying compounds, and combinations thereof.
 28. The process of claim24 wherein said step of adding an amount of DIICS to said crepingadhesive further comprises the step of adding an amount of DIICS to saidcreping adhesive prior to said creping adhesive being applied to asurface of said Yankee drum drying system.
 29. The process of claim 24wherein said step of adding an amount of DIICS to said creping adhesivefurther comprises the step of adding an amount of DIICS to said crepingadhesive after said creping adhesive has been applied to a surface ofsaid Yankee drum drying system.
 30. The process of claim 29 wherein saidstep of adding an amount of DIICS to said creping adhesive after saidcreping adhesive has been applied to a surface of said Yankee drumdrying system further comprises the step of continuously applying saidDIICS to said creping adhesive.
 31. The process of claim 24 wherein saidstep of adding an amount of DIICS to said creping adhesive furthercomprises the step of applying said amount of DIICS to said surface ofsaid Yankee drum drying system prior to said creping adhesive beingapplied to said surface of said Yankee drum drying system.
 32. Theprocess of claim 31 wherein said step of applying said amount of DIICSto said surface of said Yankee drum drying system prior to said crepingadhesive being applied to said surface of said Yankee drum drying systemfurther comprises the step of continuously applying said DIICS to saidsurface of said Yankee drum drying system.
 33. The process of claim 24wherein said step of step of adding an amount of DIICS to said crepingadhesive further comprises the step of adding an amount of DIICS to saidcreping adhesive to modify the glass transition temperature of saidcreping adhesive.
 34. A process for manufacturing a creped web materialon a papermaking machine having a Yankee drum drying system, whereinsaid process comprises the steps of: a) producing said web material withsaid papermaking machine; b) measuring a molar amount of a monovalentinorganic ionizable cation species (MIICS) in said web material; a)measuring a molar amount of a divalent inorganic ionizable cationspecies (DIICS) in said web material; b) calculating a molar ratio ofsaid measured molar amount of said MIICS to said measured molar amountof said DIICS in said web material; e) determining if said molar ratioof MIICS to DIICS is about less than or equal to 10; and, f) if saidmolar ratio of MIICS to DIICS is greater than about 10, applying anamount of DIICS to said web material after said web material has beenadhered to a surface of said Yankee drum drying system to adjust saidmolar ratio of MIICS to DIICS so said web material adhered to saidYankee drum drying system has a molar ratio of MIICS to DIICS of aboutless than or equal to 10.